Graphite Fiber and Boron Nitride Fiber Filled Potting Compounds
Abstract
Preliminary information and data are presented which show how the thermal, electrical, and mechanical properties of epoxy potting compounds may be controlled by the addition of discontinuous fibrous reinforcements of high modulus graphite and/ or boron nitride (BN). The addition of 16 parts per hundred (pph) of nominal 3 mil long graphite fibers of 83 x 106 psi modulus decreased the linear thermal coefficient of expansion (alpha) of an epoxy by 77% (from 54.3 x 10-6 in/in/C to 12.3 X 10-6 in/in/C). For the high modulus graphite fiber modification compared to the unfilled epoxy potting compound, modulus was increased by a factor of approximately 2.8 (0.46 x 106 psi to 1.28 x 106 psi) while strength was only marginally increased (15.7 x 103 psi to 16.3 x 103 psi). BN fiber additions, up to 14 pph, had little effect on modulus or strength; however, for the 14 pph addition alpha was reduced by approximately 40%. Density for the highest loaded epoxy (16 pph) containing the densest fiber modifier (graphite) with P=2.0 g/cc) was only increased by approximately 5.5% over the unfilled epoxy potting compound. All potting formulations were of pourable consistency indicating good filling characteristics.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1973
- Accession Number
- AD0913231
Entities
People
- R. J. Dauksys
Organizations
- Air Force Research Laboratory